<template>
  <div :class="classes">
    <div :class="[prefixCls+ '-list']"
         ref="hours">
      <ul :class="[prefixCls + '-ul']">
        <li :class="getCellCls(item)"
            v-for="(item,id) in hoursList"
            v-show="!item.hide"
            :key="id"
            @click="handleClick('hours', item)">{{ formatTime(item.text) }}</li>
      </ul>
    </div>
    <div :class="[prefixCls+ '-list']"
         ref="minutes">
      <ul :class="[prefixCls + '-ul']">
        <li :class="getCellCls(item)"
            v-for="(item,id) in minutesList"
            v-show="!item.hide"
            :key="id"
            @click="handleClick('minutes', item)">{{ formatTime(item.text) }}</li>
      </ul>
    </div>
    <div :class="[prefixCls+ '-list']"
         v-show="showSeconds"
         ref="seconds">
      <ul :class="[prefixCls + '-ul']">
        <li :class="getCellCls(item)"
            v-for="(item,id) in secondsList"
            v-show="!item.hide"
            :key="id"
            @click="handleClick('seconds', item)">{{ formatTime(item.text) }}</li>
      </ul>
    </div>
  </div>
</template>

<script>
import Options from '../time-mixins'
import { deepCopy, scrollTop, firstUpperCase } from '../utils'

const prefixCls = 'ivu-time-picker-cells'
const timeParts = ['hours', 'minutes', 'seconds']

export default {
  name: 'TimeSpinner',
  mixins: [Options],
  props: {
    hours: {
      type: [Number, String],
      default: NaN
    },
    minutes: {
      type: [Number, String],
      default: NaN
    },
    seconds: {
      type: [Number, String],
      default: NaN
    },
    showSeconds: {
      type: Boolean,
      default: true
    },
    steps: {
      type: Array,
      default: () => []
    }
  },
  data () {
    return {
      spinerSteps: [1, 1, 1].map((one, i) => Math.abs(this.steps[i]) || one),
      prefixCls: prefixCls,
      compiled: false,
      focusedColumn: -1, // which column inside the picker
      focusedTime: [0, 0, 0] // the values array into [hh, mm, ss]
    }
  },
  computed: {
    classes () {
      return [
        `${prefixCls}`,
        {
          [`${prefixCls}-with-seconds`]: this.showSeconds
        }
      ]
    },
    hoursList () {
      let hours = []
      const step = this.spinerSteps[0]
      const focusedHour = this.focusedColumn === 0 && this.focusedTime[0]
      const hour_tmpl = {
        text: 0,
        selected: false,
        disabled: false,
        hide: false
      }

      for (let i = 0; i < 24; i += step) {
        const hour = deepCopy(hour_tmpl)
        hour.text = i
        hour.focused = i === focusedHour

        if (this.disabledHours.length && this.disabledHours.indexOf(i) > -1) {
          hour.disabled = true
          if (this.hideDisabledOptions) hour.hide = true
        }
        if (this.hours === i) hour.selected = true
        hours.push(hour)
      }

      return hours
    },
    minutesList () {
      let minutes = []
      const step = this.spinerSteps[1]
      const focusedMinute = this.focusedColumn === 1 && this.focusedTime[1]
      const minute_tmpl = {
        text: 0,
        selected: false,
        disabled: false,
        hide: false
      }

      for (let i = 0; i < 60; i += step) {
        const minute = deepCopy(minute_tmpl)
        minute.text = i
        minute.focused = i === focusedMinute

        if (
          this.disabledMinutes.length &&
          this.disabledMinutes.indexOf(i) > -1
        ) {
          minute.disabled = true
          if (this.hideDisabledOptions) minute.hide = true
        }
        if (this.minutes === i) minute.selected = true
        minutes.push(minute)
      }
      return minutes
    },
    secondsList () {
      let seconds = []
      const step = this.spinerSteps[2]
      const focusedMinute = this.focusedColumn === 2 && this.focusedTime[2]
      const second_tmpl = {
        text: 0,
        selected: false,
        disabled: false,
        hide: false
      }

      for (let i = 0; i < 60; i += step) {
        const second = deepCopy(second_tmpl)
        second.text = i
        second.focused = i === focusedMinute

        if (
          this.disabledSeconds.length &&
          this.disabledSeconds.indexOf(i) > -1
        ) {
          second.disabled = true
          if (this.hideDisabledOptions) second.hide = true
        }
        if (this.seconds === i) second.selected = true
        seconds.push(second)
      }

      return seconds
    }
  },
  methods: {
    getCellCls (cell) {
      return [
        `${prefixCls}-cell`,
        {
          [`${prefixCls}-cell-selected`]: cell.selected,
          [`${prefixCls}-cell-focused`]: cell.focused,
          [`${prefixCls}-cell-disabled`]: cell.disabled
        }
      ]
    },
    chooseValue (values) {
      const changes = timeParts.reduce((obj, part, i) => {
        const value = values[i]
        if (this[part] === value) return obj
        return {
          ...obj,
          [part]: value
        }
      }, {})
      if (Object.keys(changes).length > 0) {
        this.emitChange(changes)
      }
    },
    handleClick (type, cell) {
      if (cell.disabled) return
      const data = {
        [type]: cell.text
      }
      this.emitChange(data)
    },
    emitChange (changes) {
      this.$emit('on-change', changes)
      this.$emit('on-pick-click')
    },
    scroll (type, index) {
      const from = this.$refs[type].scrollTop
      const to = 24 * this.getScrollIndex(type, index)
      scrollTop(this.$refs[type], from, to, 500)
    },
    getScrollIndex (type, index) {
      const Type = firstUpperCase(type)
      const disabled = this[`disabled${Type}`]
      if (disabled.length && this.hideDisabledOptions) {
        let _count = 0
        disabled.forEach(item => (item <= index ? _count++ : ''))
        index -= _count
      }
      return index
    },
    updateScroll () {
      this.$nextTick(() => {
        timeParts.forEach(type => {
          this.$refs[type].scrollTop =
            24 * this[`${type}List`].findIndex(obj => obj.text === this[type])
        })
      })
    },
    formatTime (text) {
      return text < 10 ? '0' + text : text
    },
    updateFocusedTime (col, time) {
      this.focusedColumn = col
      this.focusedTime = time.slice()
    }
  },
  watch: {
    hours (val) {
      if (!this.compiled) return
      this.scroll('hours', this.hoursList.findIndex(obj => obj.text === val))
    },
    minutes (val) {
      if (!this.compiled) return
      this.scroll('minutes', this.minutesList.findIndex(obj => obj.text === val))
    },
    seconds (val) {
      if (!this.compiled) return
      this.scroll('seconds', this.secondsList.findIndex(obj => obj.text === val))
    },
    focusedTime (updated, old) {
      timeParts.forEach((part, i) => {
        if (updated[i] === old[i] || typeof updated[i] === 'undefined') return
        const valueIndex = this[`${part}List`].findIndex(
          obj => obj.text === updated[i]
        )
        this.scroll(part, valueIndex)
      })
    }
  },
  mounted () {
    this.$nextTick(() => (this.compiled = true))
  }
}
</script>
